Remark 38.24.4. Tracing the proof of Lemma 38.24.3 to its origins we find a long and winding road. But if we assume that
f is of finite type,
\mathcal{F} is a finite type \mathcal{O}_ X-module,
E = X_ s, and
S is the spectrum of a Noetherian complete local ring.
then there is a proof relying completely on more elementary algebra as follows: first we reduce to the case where X is affine by taking a finite affine open cover. In this case Z exists by More on Algebra, Lemma 15.20.3. The key step in this proof is constructing the closed subscheme Z step by step inside the truncations \mathop{\mathrm{Spec}}(\mathcal{O}_{S, s}/\mathfrak m_ s^ n). This relies on the fact that flattening stratifications always exist when the base is Artinian, and the fact that \mathcal{O}_{S, s} = \mathop{\mathrm{lim}}\nolimits \mathcal{O}_{S, s}/\mathfrak m_ s^ n.
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